where -estimate- is the estimate, -estmsd- and -estpsd- are estimates plus
and minus the SD (respectively), and -x- is the variable against which the
estimates should be plotted. This is done in a data set with 1 observation
per group and data on estimates and SDs. Such a data set might be created
by the official Stata -collapse- command, or by the -xcollapse- package,
downloadable from SSC.